1042SCG – Genetics & Evolutionary Biology | Module 1 Lecture 1

50 Q&A-style flashcards covering administrative details, course modules, cell structure, gene expression, cell cycle, mitosis, binary fission, genetics terminology, and ploidy from Module 1 Lecture 1 notes.

Name the four molecules of life highlighted in the lecture.

Lipids, proteins, carbohydrates, and nucleic acids.

Define a prokaryotic cell in terms of DNA location.

Its DNA is not enclosed in a membrane; it resides in a nucleoid region.

Define a eukaryotic cell in terms of DNA location.

DNA is contained within a membrane-bound nucleus.

List two structures shared by both prokaryotic and eukaryotic cells.

Plasma membrane and ribosomes (also cell wall in some cases).

Give two unique features of prokaryotic cells.

Generally <5 µm and divide by binary fission; usually one circular chromosome.

Give two unique features of eukaryotic cells.

Possess membrane-bound organelles and divide by mitosis or meiosis; chromosomes are linear and multiple.

What is the size range for typical eukaryotic cells?

Approximately 10–100 µm.

What is the central dogma of molecular biology?

Information flows from DNA to RNA to protein.

Where does transcription occur in a eukaryotic cell?

Inside the nucleus.

Where does translation occur in a eukaryotic cell?

On ribosomes in the cytoplasm (free or on rough ER).

Proteins destined for secretion are translated on which ribosomes?

Ribosomes bound to the rough endoplasmic reticulum.

Is the nuclear membrane impermeable?

False – nuclear pores allow regulated exchange.

Define genome.

The complete DNA content of a cell.

Define chromosome.

A DNA molecule with associated proteins; prokaryotes usually have one circular chromosome, eukaryotes several linear chromosomes.

Define gene.

A discrete hereditary unit consisting of a specific nucleotide sequence in DNA.

Why must cells divide? Give two reasons.

For growth/repair in multicellular organisms and reproduction in unicellular organisms.

What are the two eukaryotic cell-division processes?

Mitosis and meiosis.

Which division process produces genetically identical daughter cells?

Mitosis.

Which division process is required for sexual reproduction?

Meiosis.

Name the two broad phases of the eukaryotic cell cycle.

Interphase and the mitotic (M) phase.

List the three stages of interphase in order.

G₁, S, G₂.

What happens during the S phase?

DNA is replicated (chromosomes are duplicated).

What key event occurs during G₂?

Cell growth, centrosome duplication, and DNA repair in preparation for mitosis.

What cellular structure organizes microtubules during mitosis?

The centrosome (with a pair of centrioles).

Give the sequence of mitotic stages using the PPMAT acronym.

Prophase, Prometaphase, Metaphase, Anaphase, Telophase (followed by cytokinesis).

Describe a hallmark of prophase.

Chromosomes condense and the mitotic spindle begins to form.

What characterizes prometaphase?

Nuclear envelope fragments and spindle microtubules attach to kinetochores.

Where are chromosomes located during metaphase?

Aligned at the metaphase plate (cell equator).

What major event defines anaphase?

Sister chromatids separate and move toward opposite spindle poles.

What happens in telophase?

Chromosomes decondense and new nuclear envelopes form around each set.

Explain cytokinesis in animal cells.

An actin-myosin ring constricts to form a cleavage furrow, dividing the cytoplasm into two daughter cells.

Outline the three major steps of binary fission.

1) DNA replication from a single origin; 2) cell elongation as origins move apart; 3) membrane pinching and septum formation to yield two cells.

How many chromosomes do human somatic cells have?

46 chromosomes (23 homologous pairs).

Define diploid.

A cell containing two sets of homologous chromosomes (2n).

Define haploid.

A cell containing one set of chromosomes (n).

What term describes organisms with more than two chromosome sets?

Polyploid.

Give an example of a polyploid organism group.

Many plant species (e.g., wheat) are polyploid.

During which mitotic stage do chromosomes first become visible under a light microscope?

Prophase.

Which cytoskeletal component forms the contractile ring in cytokinesis?

Actin microfilaments.

What is the function of kinetochores?

They serve as attachment sites for spindle microtubules on chromosomes.

State Learning Outcome 6 for the course.

Describe the process and concepts of evolution.

What laboratory safety items must students bring for the Week 8 lab?

Safety glasses, lab coat, enclosed shoes; long hair tied back.

Which online platform hosts course modules, assessments, and resources?

Canvas (Griffith University).

Which reference text is recommended (but not required) besides Campbell Biology?

Snustad & Simmons ‘Principles of Genetics’ or Pierce ‘Genetics: A Conceptual Approach’.